In the process of dry hopping a belgian tripel my hop bags came open in the secondary and some pellets were released into the secondary. How long will it take the hops to settle out, or am I going to have hop pieces in the beer?

If you place the carboy in the refrig or cooler the hops will drop out of suspension allowing you to siphon off the beer. You may loose a little because the hops won't compact like yeast but you won't be straining hops through your teeth.